Considering the above, a research work was done by Applicants with the view to depress or eliminate the disagreable organoleptic characteristics of the drug described above without impairing its pharmacologically useful properties. It was thus unexpectedly found that Fominoben may be complexed with theophyllinein equimolar proportion and the obtained complex fully solves the problem. It was known that theophylline has analeptic properties on respiratory activity and is exempt of antagonistic side effects, toxicity and teratogenic effects. However, it is to be noted that in practical dosage of the said complex the amount complexed theophylline is far below the therapeutical doses of theophylline used in the prior art, so that there was no logical reason to complex Fominoben with theophyllin with the view to obtain detectable therapeutical benefits, and still less is was expectable that the complex will no longer exhibit the disagreable organoleptic characteristics of Fominoben.